JPH0221809B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the invention described in U.S. Patent Application No. 562,309, filed December 16, 1983.
This application is incorporated herein by reference in its entirety.

The invention is herein incorporated into an assembly for collecting a liquid sample from a patient, such as a blood sample. More particularly, the present invention relates to a needle assembly that collects single or multiple fluid samples from a patient using a single assembly.

This device utilizes a sample housing chamber with transparent or translucent walls for observing whether adequate access to the desired sample source is achieved.

In addition, a highly absorbent material for water-containing solutions is used in a generally cylindrical sleeve to allow the passage of gases that are displaced by the liquid sample moving into the housing chamber, and once exposed to the liquid sample. , the material immediately swells and prevents the liquid sample from expelling from the housing chamber. The sleeve is comprised of a solid, compressed material and is sized to permit the passage of air between the wall of the sleeve and the adjacent wall of the housing containing the sleeve. This material contacts the liquid and closes the outflow passage.

As explained in the aforementioned co-pending application,
The tablet forming a cylindrical sleeve is adapted to seal the chamber against the escape of the sample, while at the same time allowing the gas displaced by the sample to pass through. as indicated by transparent or translucent chamber walls to observe the presence of the sample in the housing chamber;
Once the inlet to the liquid sample has been created, multiple samples can be collected from the housing chamber by successively withdrawing them into multiple vacuum collection devices. This assembly incorporates a separate flexible self-sealing resilient sleeve that cooperates with the evacuation opening of the vacuum collection device during replacement of the device to eject successive samples.

In some cases, when using the compressed tablet sleeve embodiment described in co-pending application Ser. It has been found that it is possible to move the tablet to one side to provide a larger opening. This can also happen simply due to gravity. In any case, this results in an instantaneous non-uniform response to the initial volume of blood, which has the effect of slightly delaying the occlusion of blood flow during the process of directing blood to the initial vein for sampling.

In contrast, the present invention places the tablet cylinder or sleeve on a tapered hub post. The taper is such that the diameter of the hub post increases toward the suction end of the device. By this,
The tablet sleeve axis is kept concentric with the cooperating boss axis, creating a device that responds uniformly over the front circumference to the sample. Therefore, when venous entry is achieved through the sleeve, after a uniform response in the initial venting configuration of the air pocket of the assembly, the evacuated sample-receiving tube is inserted into the negative cannula end of the assembly. Immediately and almost simultaneously, the compressed sleeve material swells and occludes blood flow before being attached to the sleeve. Thus, the moment blood contacts the sleeve, the sleeve expands uniformly and concentrically around its hub post by absorbing moisture from the blood sample to prevent movement past the sleeve.

As mentioned above, it is desirable to provide a mechanism by which a user of a needle assembly can be told when an intravenous needle has entered a sample collection source, such as a patient's vein, for collecting a blood sample. . In many cases where blood is drawn from a patient, the vein is difficult to locate or there is insufficient blood flow to the collection device for other reasons. In these cases, it is advantageous to quickly determine that a vein has been entered so that the decision to direct blood into the needle assembly can be made quickly. Once this determination has been made and venous entry has been made, an evacuated blood collection container is inserted into the collection assembly according to known blood sample collection methods during a collection operation consisting of a single venous entry. You can.

The present invention is directed here to solving one of the problems that occurs during venipuncture: the presence of air pockets in various needle assemblies. When performing a venipuncture, because the evacuated blood collection container has not yet been attached to the opposite end of the structure, under normal pressure conditions blood will be removed due to the air pocket remaining inside the needle assembly. cannot flow into the needle assembly. Therefore, even if a vein is entered, blood will not begin to flow simply due to obstruction of the air pocket in the assembly.

U.S. Patent No. 1, assigned to a common assignee with this application.
Nos. 4,207,870 and 4,398,544 use porous plugs in blood collection assemblies of the type described herein. All of these devices use materials that are air permeable but liquid impermeable. Both of these patents describe inventions using relatively complex valve structures with internal components. Although these inventions allow for the use of porous materials to pass air that is displaced during blood sample storage, there is still room for improvement in such devices. That is, although treatment by physical closure is generally effective, it is not always possible to achieve complete sealing.

In the present invention, by contrast, the material is in the form of a separate sleeve or tablet that can be mechanically inserted between the two parts forming the housing during assembly on the production line. The device in the text is
It is a simplified structure consisting of a cylindrical highly absorbent material that swells on contact with aqueous substances. The material is a highly absorbent material compressed into a sleeve-like cylindrical tablet that is mechanically inserted between the two parts forming the housing. As will be appreciated by those skilled in the art of manufacturing multiple blood collection assemblies,
These cylinders can be manufactured separately in large numbers and inserted between the two parts forming the housing on a mass production line, all of which is handled by robots.

Before describing the present invention in detail, it is important to note that the material forming the generally cylindrical vent sleeve of the present invention is manufactured by Grain Processing Corporation (Grain Processing Corporation).
WATER-LOCK, a product of Processing Corporation, 1600 Oregon Street, Muscatine, Iowa 52761.
It should be noted that it may consist of a hydrolyzed starch-polyacrylonitrile graft copolymer having side chains containing carboxamide and carboxylate groups, such as A100 or Waterlock A125. Other material sources include Henkel Corporation (Henkel Corporation)
Super Absorbent Company, 4620 West 77th Street, Minneapolis, Minnesota;
Absorbent Company, Route 3, PO Box 342, Lumberton, North Carolina; and Edison Hydrocontrol Chemicals, Inc.
Chemicals Inc.). 99 Madison Street
Avenue), New York 10016.

The water-absorbing polymer composition of the present invention is disclosed in U.S. Pat.
No. 4045387, No. 4134863, No. 3981100, No.
No. 4159260, No. 3661815, No. 3935099 and No.
It can be produced by the method described in No. 3985616.

Referring to the drawings, like reference numerals refer to like parts throughout the several figures. 1st
The illustrations show a housing 12, a first intravenous needle (IV) cannula 14 for insertion into a patient, and a second negative pressure needle cannula 1 at the opposite end of the housing 12.
5 shows the basic external components of needle assembly 10, including 5 and 5. The second needle cannula 15 is suitable for insertion into an evacuated or negative pressure container 16 for collecting a blood sample. Those skilled in the art should
It will be appreciated that as an alternative to the dual needle assemblies 14, 15 described herein, a single needle structure extending through the assembly may be used. The twin needle assembly described is merely illustrative of the context of the invention. The housing 12 includes a negative pressure boss portion 25 having a thread 18 near the second cannula.
, onto which a container holder 19 is screwed by means of a screw 20 which engages inside the front end of the holder. The evacuated container 16 is inserted into the holder 19 so that the second needle cannula 15 pierces the stopper 21 at the front end of the evacuated container 16. The general appearance of these blood sample collection assemblies is well known to those skilled in the art.

Referring to FIG. 2, vacuum boss portion 25 of housing 12 is shown. The negative pressure boss includes a cylindrical portion 111 adapted to cooperate with the anterior intravenous boss 24 as described below. Flange 46 is also positioned to cooperate with flange 88 on anterior intravenous boss 24, as described below. A hole 70 extends into the rear end 25 of the housing. hole 70
is large enough to accommodate the diameter of the second needle cannula 15 and is secured in the hole 70 by any suitable method, e.g. with adhesive.
Figure). As discussed in more detail below, it is within the scope of the invention to join the two bosses together by sonic welding or other suitable joining methods known in the art.

As can be seen in Figure 2, negative pressure cannula 15
terminates at a point 100 positioned to pierce the stopper 21 of the evacuated container 16. A flange 9 covers the negative pressure end of the cannula 15.
2. A self-sealing elastic sleeve 80 with 2 parts. Thus, when point 100 penetrates the central penetrable septum of stopper 21, point 100 first penetrates the distal end of flexible sleeve 80 and collapses sleeve 80, as shown in FIG. In this regard, the inner surface of flange 92 adjacent cannula 15 includes a portion (not shown) for engaging an annular snap-on barb 177 of extension 26. This causes sleeve 80 to engage cannula 15 with a snap fit. It will be appreciated that other topologies may also be used.

Referring now to FIG. 5, the intravenous boss 24 includes a bore 29 for receiving the intravenous cannula 14. Boss 24 includes a rear extension 117 having a larger diameter to define a housing chamber 50 for containing a blood sample. At the rear of the extension 117, there is further a bias 119 at the junction of the chamber 50 and the hole 108;
Cylindrical section 118 forming larger internal bore 108
are integrally formed.

The hole 29 communicates with the chamber 50.
The hole 30 is of smaller diameter. Offset 33 between holes 29 and 30 serves as a seat for the inner end of intravenous cannula 14. Extending around the front of the boss 24 are a plurality of ribs 31 that cooperate with internal ribs on the shield (not shown) that are connected to the intravenous needle cannula 14.
It is used to cover the material until it is used.

The vacuum boss 25 forward of the flange 46 includes an integrally formed forward cylindrical extension 111 followed by a forward integrally formed cylindrical extension or hub post 109 . hub post 109
has a smaller diameter than the extension 111, forming an offset 110 therebetween. The hub post 109 cooperates with the rear extensions 117, 118 of the intravenous boss 24 to form an annular outflow passageway 120 and an annular chamber 51.
form. The annular chamber 51 forms the portion that accommodates the sleeve or tablet 116 compressed onto the hub post 109 of the present invention as described below. Chamber 51 also serves as a chamber for indicating entry into the vein since the walls of extensions 117 and 118 are transparent or translucent. As mentioned above, sleeve 116 may be comprised of compressed WATER-LOCK A125, a product of Grain Processing Corporation. As shown in FIG.
are the rear extensions 117, 118 of the intravenous boss 24.
Before inserting the hub post 10 of the negative pressure boss 25
It may be formed and arranged on 9.

According to the invention, the hub post 109 has a cylindrical compressed tablet or sleeve 116.
It has a columnar boss shape that supports the. Additionally, hub post 109 has a tapered surface 114 such that columnar boss 109 gradually increases in diameter in the suction direction from point 129 to offset 110. This provides a wedging effect between the tablet sleeve 116 and the surface 114, supporting the tablet sleeve 116 concentrically against the wall of the chamber 51 and the surface 114. Therefore, the tablet sleeve 116 responds equally with each annulus expansion, allowing the air pocket to flow out of the device and immediately swells upon contact with sample moisture.

5, the central extension 111 of the vacuum boss 25 has a diameter slightly smaller than the diameter of the bore 108 and is disposed on a flange 88 forming the most distal end of the intravenous boss 24. A ventilation passage 122 communicating with the ventilation section 104 is formed. Flanges 46, 88 are joined together into a complete assembly by sonic welding at passageway 102. Those skilled in the art will also appreciate that the cooperating grooves 140 and extensions 141 formed in the cooperating flanges 46, 88 can be joined together, for example, by adhesive material.

For purposes of illustration only, passageway 120 between chamber 50 and chamber 51 may have a radius of 0.04 mm (0.0015 inch). That is,
The diameter of the forward end of the hub post 109 is 2.8 mm (0.110 inch) and the annular extension 11 of the intravenous boss 24
The diameter of the chamber 50 formed by 7 is 2.9 mm.
(0.113 inch). Outflow passage radius is 0.04mm
(0.0015 inch), but preferably 0.01 mm
(0.0005 inch). That is, the extension section 11
The diameter of hole 1 is 5.5 mm (0.217 inch);
The diameter of the 08 is 5.6 mm (0.220 inch).

Further, purely for illustration purposes, the length of hub post 109 is 7.1 mm (0.28 inch), while the length of tapered surface 114 is 3.9 mm.
(0.155 inch). The angle of surface 114 from extension 109 is 1.2°.

That is, it is a Brown-Sharp type taper with a diameter of 12.7 mm (0.500 inch) per 30 cm (1 foot) of length. For a compressed tablet or sleeve 116, the length is approximately
Within the range of 2.8mm to 3.8mm (0.110 to 0.149 inch).

The inner diameter of the central opening or hole 112 in the sleeve 116 is not particularly critical to the invention, so long as it is of a suitable length to secure the desired wedge/or sheeting in the extension 109. For example, hole 11
2 may be within the range of approximately 0.111 to 0.114 inches. A critical dimension is the gap between the outer surface of sleeve 116 and the wall of chamber 51. Generally, the diametrical gap is about 0.003~0.10mm
(0.0001 inch to 0.004 inch), preferably 0.01 to 0.10 mm (0.0005 inch to
0.004 inch). Preferably, there is a gap to initially maintain some degree of breathability within a very small range, including the swelling reaction of the sleeve or tablet 116 upon contact with moisture. The tablet or sleeve 116 is comprised of compressed powder and is compressed in a die to a density within the range of approximately 0.80 to 1.1 g/cc. This powder is manufactured by U.S. Patent No.
3661815 or 4159260, which is a product of Grain Processing Corporation.
It is named LOCK (trademark) A125. This material is a starch-graft copolymer of polyacrylic acid and polyacrylamide. This is 0.34 g/min before being compressed into the tablet sleeve of the present invention.
It has a density of cc. Waterlock A125 is
This is just one example of a typical product used to mold the sleeve 116.

Turning now to FIG. 6, a representative apparatus for forming the tablet or sleeve 116 of the present invention is shown. It should be understood that this is for illustration purposes only and that other equipment may be used to compact the representative powder to the desired density. For example, the die 152 is connected to the locating pin 154.
is shown disposed on spacer 162 by. Pin 154 is held to die 152 by a set screw 160. A pin 154 is centrally located in the hole 164 for cooperating with a push rod 156 to form the tablet or sleeve 116 of the present invention. The density of tablets 116 formed by such equipment depends on the stroke length and/or
Or it will be appreciated that this may vary by varying the dimensions of the filler used.

As can be seen from the foregoing description, the blood collection needle assembly of the present invention can be used to collect single and multiple blood samples from a single venous entry point, if desired in combination with a device that alerts the user of the assembly to venous entry. Provided for collecting samples. In this regard, tablet- or sleeve-type devices may be useful because the presence of blood in the sleeve is indicated through the transparent or translucent housing wall, and thus the presence of blood in the chamber of the assembly is ``indicative''. Helpful. Due to its size, degree of compaction and/or density, the material readily absorbs blood moisture and swells to the point where it seals the chamber in the housing and prevents leakage of blood. This allows venous blood to flow from the blood source into the housing chamber substantially immediately after the remaining air in the housing chamber has been purged.

The tapered hub post on which the compressed tablet rests holds the tablet in proper alignment and concentricity with the chamber wall and containing hub post, and once the air passages have been created, each portion of the powder forming the tablet reacts simultaneously with the moisture introduced into the chamber and swells rapidly, closing the air passage and preventing sample leakage.

Therefore, indicating or indicating to the user that displacement air has exited the chamber, the chamber has been sealed, and the patient's veins have been properly entered to collect multiple samples, It happens almost instantaneously and simultaneously. Following this display, the user sequentially connects the plurality of tubes 16 to the negative pressure cannula 1 having the sleeve valve 80.
5 and subsequent removal and another evacuated tube 1
6 to provide a self-sealing device for collecting multiple blood samples from a single blood source in a single venipuncture.

The device described herein is, of course, a disposable device. Once a single or multiple samples have been taken from a single blood source, they are discarded. In this regard, the device is a very inexpensive and simplified device that can be used in mass production lines with a separate sleeve between the two parts forming the housing as a separate part of the assembly. It is important to understand that literally thousands of assemblies of the present invention can be produced with high efficiency in a highly mechanized manner. However, although these devices are inexpensive and disposable, they signal venous entry, allow displacement air to exit, and, once venous entry is indicated by the device, properly open the housing chamber. Accurately and reliably performs the function of completely sealing.

Although the device methods and configurations described above constitute preferred embodiments of the invention, the invention is not limited to these precise device methods and configurations;
Changes may be made without departing from the scope of the claims.

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view schematically showing standard parts and equipment of a sample collection needle assembly comprising a holder for a negative pressure container and a negative pressure blood collection container used to obtain a blood sample from a patient; Yes, Figure 2 is the same as Figure 1.
FIG. 3 is an enlarged partial cross-sectional view taken along line 2--2 of FIG. 1 and showing a separate resilient sleeve valve for use in the assembly; FIG. 4 is a perspective view of the needle assembly connected to a holder inserted into a patient so that the user can observe the assembly's entry into a vein, and FIG. 2 is an enlarged cross-sectional view of the housing assembly of FIG. 1 with the cannula removed, showing a housing having a venous boss, a negative pressure boss, and a tapered support hub post of the present invention, which is an embodiment of a sleeve, formed therebetween; FIG. FIG. 6 is a cross-sectional view of an apparatus for forming a compressed cylindrical sleeve or tablet forming part of the present invention. 10: needle assembly, 12: housing, 14,1
5: needle cannula, 16: negative pressure container, 18: screw, 19: container holder, 20: screw, 21: stopper, 24: intravenous boss section, 25: negative pressure boss section, 26: extension section, 29: hole , 46: flange,
50: Housing chamber, 111: Cylindrical part.

Claims (1)

Claims: 1. A needle assembly for collecting one or more liquid samples from a sample source and then discharging the samples into a negative pressure container, the housing having a front end and a rear end. a sample collection chamber in the housing; a first inlet opening in the forward end in fluid communication with the sample collection chamber; and a first inlet opening for insertion into the sample source. a first cannula extending outwardly from the aperture; a second inlet aperture at the rear end communicating with the sample collection chamber; and a second inlet aperture at the second inlet aperture. a second cannula in communication with the sample collection chamber; and a second cannula disposed in the second cannula for discharging a liquid sample from the sample collection chamber into a negative pressure vessel attached to the second cannula. and a valve device provided at the front end and the rear end of the housing to provide a fluid outflow passage therebetween, and a valve device provided at the rear end to provide a fluid outflow passage between the front end and the rear end of the housing. a cooperating device having a tapered hub post extending into the sample collection chamber with a cross section that gradually increases toward the rear end; an annular compressed sleeve disposed on the hub post and made of a material that swells upon contact with a moisture-containing material introduced into the sample collection chamber and acts to close the fluid exit passage; , whereby when the first cannula engages the sample source, a liquid containing water enters the sample collection chamber and directs gas in the sample collection chamber between the fluid exit passageway and the venting device. a needle assembly configured to cause the liquid to contact the sleeve and cause it to swell and close the fluid exit passageway. 2. The needle assembly of claim 1, wherein the cooperating device comprises: an integrally formed cylindrical extension at the rear end of the housing; and an integral cylindrical extension at the front end of the housing. an integrally formed annular extension, wherein an inner surface of the extension of the front end and an outer surface of the rear end cooperate to form an annular fluid outflow passage therebetween. Three-dimensional. 3. The needle assembly of claim 1, wherein the sleeve comprises an annular compressed sleeve of hydrolyzed starch-polyacrylonitrile graft copolymer having side chains containing carboxamide and carboxylate groups. A needle assembly comprising: 4. The needle assembly of claim 3, wherein the annular sleeve has a weight of about 0.80 to 1.1 g/
A needle assembly characterized in that it consists of a powder compacted to a density in the range of cc. 5. The needle assembly of claim 1, wherein the distance of the loose fit between the compressed sleeve and the wall of the chamber containing the sleeve is approximately
A needle assembly characterized in that it is within the range of 0.003mm to 0.1mm. 6. The needle assembly of claim 5, wherein the loose fit is within the range of about 0.01 mm to 0.1 mm. 7. Needle assembly according to claim 1, characterized in that the housing comprises a device for connecting a holder of a negative pressure container. 8. The needle assembly according to claim 1, further comprising a negative pressure container holder connected to the housing. 9. A needle assembly according to claim 1, further comprising a device for observing the contents of the sample collection chamber. 10. The needle assembly of claim 9, wherein the viewing device is a transparent or translucent housing wall proximate the sample collection chamber. 11. The needle assembly of claim 1, wherein the hub post has a tapered surface, the tapered surface having an angle of 1.2° from the axis of the hub post. Features needle assembly. 12. The needle assembly of claim 11, wherein the length of the tapered surface is 3.9 mm. 13. The needle assembly of claim 1, wherein the annular compressed sleeve has a diameter in the range of about 2.8-2.9 mm.